Rare Infection Threatens to Spread in Blood Supply

NY Times ^ | 11/18/03 | Donald G. McNeil Jr

[neverdem]

A parasitic infection common in Latin America is threatening the United States blood supply, public health experts say. They are especially concerned because there will be no test for it in donated blood until next year at the earliest.

The infection, Chagas disease, is still rare in this country. Only nine cases are known to have been transmitted by transfusion or transplant in the United States and Canada in the last 20 years.

But hundreds of blood recipients may be silently infected, experts say, and there is no effective treatment for them. After a decade or more, 10 to 30 percent of them will die when their hearts or intestines, weakened by the disease, explode.

Chagas is still little known in the United States, but in Mexico, Central America and South America, 18 million people are infected, and 50,000 a year die of it.

Experts expect it to become better known as new tests are developed.

"I wouldn't say that it's as rare as hen's teeth, but it's rare," said Dr. Ravi V. Durvasula, a Chagas expert at the Yale School of Public Health. "It's one of the top threats to the blood supply, but it's an emerging threat."

Because the disease is most common in rural areas from southern Mexico to northern Chile, the threat is greatest in American cities with many immigrants from those areas.

Across the United States, said Dr. David A. Leiby, a Chagas expert at the American Red Cross, the risk of getting a transfusion of infected blood is only about 1 in 25,000.

But in 1998 in Miami it was found to be 1 in 9,000, he said, and in Los Angeles the same year, he measured it at 1 in 5,400, up from 1 in 9,850 only two years earlier.

No more recent study of the blood supply has been done.

The only routine screening for Chagas now is in the standard set of questions asked of donors — whether they come from or have visited a country where Chagas is endemic and whether they ever slept in a thatched hut.

But that often isn't reliable, said Dr. Louis V. Kirchhoff, a professor at the University of Iowa's medical school who researches Chagas in Guadalajara, Mexico, where the chance of getting infected blood is 1 in 126. Potential donors "are kind of leery of those questions," he said, and may not answer honestly.

Since 1989, several advisory panels to the United States Food and Drug Administration have recommended that all donated blood be screened for Chagas. But no test has been approved yet.

Last year, the F.D.A. invited diagnostics companies to create one, and the two largest, Abbott Laboratories and Ortho-Clinical Diagnostics, are trying. But representatives of the companies said they were under little deadline pressure. Abbott's test may be ready next year.

Little sense of urgency exists because "there are always new things that come up," Dr. Leiby said. Hepatitis and AIDS were followed by mad cow disease, West Nile virus and bacterial contamination of platelets, so "Chagas gets pushed to the side," he said.

Mary Richardson, a spokeswoman for Ortho, which hopes to have a test by 2005, added: "Clinical trials take time. There's only so much speeding up you can do."

Nonetheless, she added, "the F.D.A. feels it's the next biggest threat."

An F.D.A. spokeswoman said her agency did not like to rank all the threats to the blood supply — including hepatitis, AIDS and West Nile virus — but reiterated that "we would certainly recommend a Chagas test if one is developed."

Prevalence rates in Latin America vary widely, from 25 percent in Bolivia to 1 percent in Mexico.

It is not found on Caribbean islands like Puerto Rico, the Dominican Republic or Cuba.

In some countries, it is a serious threat to the blood supplies; in one Bolivian city, half of the blood was infected.

About 30 tests are used in different countries, but none meet F.D.A. accuracy standards. Some Latin American blood banks disinfect with gentian violet, but it is unpopular because it gives recipients a purplish tinge.

(Page 2 of 2)

The disease is named for Carlos Chagas, the Brazilian doctor who described it in 1909. It is caused by a protozoan, Trypanosoma cruzi, which infects humans in a particularly disgusting way. Reduviids, also called kissing or assassin bugs, drop down from the thatch, follow the trail of carbon dioxide to the mouths of sleeping humans and suck their blood. They leave behind a protozoan-laden drop of feces, which the sleeper often inadvertently rubs into the itching wound.

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Charles Darwin may have been infected on his travels; he suffered with Chagas symptoms for many years in England.

There is no vaccine and no effective treatment. The first phase, which starts within weeks of infection, may include fever and swollen glands, liver or spleen, but is rarely fatal except in infants and in adults with compromised immune systems. It is often misdiagnosed.

The disease can then lie dormant for 10 to 30 years, then kill suddenly as weakened organs rupture.

The failure of the blood industry and its regulators to develop a test since it was endorsed by a Blood Products Advisory Committee in 1989 seems to be a combination of bureaucratic inertia and divided responsibility for such a decision. Blood banks cannot use a test that the F.D.A. has not approved. The agency usually defers to its advisory committees, which have many experts from blood banks as members.

"It's a political process that is not always fully engaged," said Dr. Stuart J. Kahn of the Infectious Disease Research Institute, a Seattle group hunting cures for tropical diseases.

Dr. Hira Nakhasi, director of transfusion-transmitted diseases at the F.D.A., agreed that neither the blood banks nor his agency had been very aggressive. Things tended to move when "the public and media put pressure on," he said.

Cost concerns made blood banks hesitant, Dr. Kirchhoff said. It may cost $50 million to $100 million a year to screen the whole United States blood supply, he estimated, and "people will reasonably say, `Why should we do this if we're not seeing a lot of sick people?' "

Although perhaps 120 Americans a year get infected blood, he said, between 70 and 90 percent will not become seriously ill, and few of those who do will live long enough to die of Chagas.

Most transfusion recipients are fairly sick, and half die of other causes within two years anyway.

But he pointed out that the risk was growing rapidly. Census figures show that net immigration from Mexico is about 1,000 people a day, he said. Of those, 5 to 10 are probably infected.

Meanwhile, blood banks increased their appeals to Hispanics in the 1990's, under extra pressure when mad cow disease eliminated donors who had made long visits to Europe and AIDS eliminated gay men and other risk groups.

Interest in Chagas seems to be growing, Dr. Kahn said, because breakthroughs in biogenetics make it easier to attack diseases and because the interest of the Bill and Melinda Gates Foundation in third world health "put a lot of diseases up on the radar screen."

[stanz]

Good grief!

[neverdem]

What a link, LOL. I vaguely remember reading about this strange critter. Thanks a lot.

[Conservababe]

Thanks for the ping. Years ago, it was possible that one person could donate his own blood directly to the designated person who needed a transfusion. Sure, it had to be processed, but it still went directly from one donor to the patient.

We can't do that anymore and I blame the Red Cross. Your donated blood must go into the bank.

But, I do remember a case in my hospital. The patient needed elective, but serious, surgery. He was of the Jehovah Witness religion. He could not receive a blood transfusion, if needed, but he could receive his own blood back, according to his beliefs. So, my hospital outpatient lab accomadated him by allowing him to donate to himself, so to speak, before the surgery. Somehow they were able to process the blood and get it back to him during surgery.

Now, why can't we do this for every patient, if possible? I would rather receive blood from someone I know, if the right type of course, than a stranger. And I would be willing to pay more the transfusion to be safe.

[NRA2BFree]

Very interesting. My stomach and lower intestines ruptured in 1989 and they could never figure out what caused it. The lab work all came back negative. I was so sick, I spent 21 days in the hospital after a six hour surgery. NM has always had a large number of illegals and it's possible I could have received bad blood from a previous surgery. I don't know that this is what it was, but it's more than we've had to go on since it happened. Thanks for posting this. I'm going to talk to my doctor about it.

[neverdem]

When folks have prolonged abdominal complaints over more than a few days, docs usually request a stool sample to check for ova and parasites.

However, that's not the case with this protozoa. They draw blood samples and might be able to visualize the organism in a microscope. If unsuccessful, there are available more sophisticated biochemical tests looking for specific anti-bodies to T. cruzi.

Contrary to this story, there are medicines to treat this condition except they may not always work and can have bad side effects.

However, most folks with this disease, if left untreated, will die from congestive heart failure or a fatal arrhythmia.

Without crapping in your pants, go see your doc, please.

I'm sorry if I scared anyone.

[Calpernia]

Linking this thread I posted a bit ago for reference: http://www.freerepublic.com/focus/f-news/889385/posts

[neverdem]

Thanks for the link. How did you retrieve it, by entering "Tainted blood" into the FR search function?

[Calpernia]

I was the poster of that thread.

[Doctor Stochastic]

Self-donation has been around for a while. I know several people who used it. It hasn't been shown that one has a better survival rate when using one's own blood. (I would think so, but the statistics just aren't ther.) Also, this procedure only applies to elective surgery. Blood has a short shelf life. The good news is the blood by products (plasma, and a few others) are generally safer than whole blood.

[neverdem]

I noticed that. I was asking how did you retrieve it? Are you maintaining a log of the titles you post?

[Calpernia]

Oh, I have it saved in my FR links.

[thepainster]

Whole blood currently has a shelf life of 42 days. Frozen blood has a shelf life of several years. Undoubtably your friend was able to donate his own blood, which was frozen, and given to him at a later date during the elective surgery.

Next question; why isn't all donated blood frozen? It is much more expensive, as it requires additional equipment to freeze and reconstitute the blood.

[Conservababe]

Yes, but we are talking about blood donors with diseases that can be transmitted. I would rather self donate or have someone I know donate to me. Of course, that would not be possible in an emergency situation.

[Conservababe]

Next question; why isn't all donated blood frozen? It is much more expensive, as it requires additional equipment to freeze and reconstitute the blood.

I would pay the expense to have a safe transfusion rather than take the chance of blood from donors who are not screened other than asking questions during the interview before drawing and a mere token screening afterwards. And I especially mistrust the donors who are paid for their blood. Seems a lot of people do not realize that all donors are not the ones who donate freely at the Red Cross drives.

[neverdem]

"Oh, I have it saved in my FR links."

How did you do that, if you don't mind explaing that?

[oldironsides]

We had US Navy crew afflicted with TB a while back. They live in close quarters and picked it up somewhere. I think there were 9 or so with it.

[itsahoot]

Why even bother having a federal government?

Some one has to collect your money.

[Calpernia]

>>>How did you do that, if you don't mind explaing that?

Oh! I get it.

When you see a thread posted that you like, RIGHT AT THE END of the posted article are two options, REPORT ABUSE and BOOKMARK

If you click BOOKMARK, it is added to your FR Profile LINKS page.

You can access these links under your profile. Top Nav link of the Profile page has a LINKS hyperlink. That will be where your saved links go.

Click my Freeper name. On my Profile Page you will see LINKS (Top Nav Bar). If you click that, you will see all the links I've saved.

[Calpernia]

See, right under Keywords:

TOPICS: Breaking News; Culture/Society; Foreign Affairs; Government; Politics/Elections; Testing; Click to Add Topic
KEYWORDS: BLOODHOUNDS; BLOODTRANSFUSION; HEALTH; HEALTHCARE; IMMIGRATION; Click to Add Keyword

---

[ Report Abuse | Bookmark ] <-----That Bookmark link will save to YOUR profile links page.

[Lighthouse Lady]

You can donate blood for your self (autologous donation) or for someone else (designated donation). You actually do pay more for this service. It is done every day. The other poster was correct, though, in saying that there is no evidence that it is safer to receive a designated donation. It is safe to receive blood from a frequent donor who is tested each and every time.
LL